F-3 and automatic transition

[Chuck Stewart]

Did the Monon's F-3's have automatic transition?  Thanks!

[Ron Marquardt]

No Chuck, they were not equipped with automatic transition.  / Ron

[Chuck Stewart]

Thanks, again, Ron.  Been reading the Spring 2015 issue of Classic Trains and specifically Preston Cook's article "F units T to 9".  I always thought that from an engineer's viewpoint that auto transition was a big deal.  But I can find no mention of it in this article.  I thought I had read somewhere that this improvement came along after the war...which is why I thought the F3's might have had it.  Was the F7 the first EMD model to have auto transition?

[Steve Dolzall]

According to the EMD Operating Manual automatic transisition was available on the model F-3. However, NOT all F-3's had that feature. It appears that automatic transisition became available on the F-3 at some latter point in the production run.

Steve

[Chuck Stewart]

Thanks, Steve!

[Stew Winstandley]

Since I had no knowledge of manual or automatic transition on locomotives, I googled transition and found a lot of information.  Since reading about transition, did the later Monon locomotives have automatic transition?  The transition on a locomotive was compared to manual and automatic transmissions on road vehicles.

When the Monon put a RS2 between C-628s on the south end, did all the units have the same transition?  Part of what I read pointed out that in a consist of locomotives, the locomotives were set to not transition together, if they did that could cause train separation. I can understand the problems with MUing different locomotives together, and in fact some comments were about the transition problems with the same model of locomotives in the same consist.

Stew

[Ron Marquardt]

Stew, the transition settings were not MU'd. Each unit did it's own thing, according to it's particular design.  I've never known of transition being so rough as to cause a train separation.  The C628's did have a unique bad habit during downward transition (about 26 or 27 mph) in that they would often trip the engine (engine, not  locomotive) overspeed, and we would have to hurry back, reset it, and restart the engine.  We eventually learned that reducing the throttle to #6 during transition would usually lessen this problem.  / Ron